This invention relates to an element which is punched out in a cover shape for sealing of containers, consisting of two plies with at least one opening aid which is integrated within these plies, the ply located in the direction of the container having a plastic layer which is provided with perforations or scoring. The invention relates furthermore to a process for producing this two-ply sealing element.
For example, the sealing of microwave containers with two-ply sealing elements is known, the outer ply being a paper or metal layer and the second ply facing the container being a plastic layer. Since the materials of the outer ply oppose the passage of microwaves, they must be removed before heating the container. The container which has now been sealed with the plastic film must then be perforated by hand in order to enable escape of water vapor during heating or cooking of the contents.